Hyperpigmentation, Familial Progressive, 1, also known as fph1, is related to hyperpigmentation with or without hypopigmentation, familial progressive and hypomagnesemia 2, renal. An important gene associated with Hyperpigmentation, Familial Progressive, 1 is HPP1 (Hyperpigmentation, Progressive, 1). Affiliated tissues include skin, and related phenotype is hyperpigmentation of the skin.